I installed the extension and it's incredibly easy to use. I tried it on a personal site, google.com, etc and it's interesting to see the various performance metrics for each site. I'd be curious to see what the highest PWA (progressive web app) score someone saw for a major website (for reference, I got 44/100 for google.com).
Tried it on www.flipkart.com (Amazon of India) and it scores 72-75/100. AliExpress scored 78.